Researchers from the Center for Environmental and Marine Studies (CESAM) at the University of Aveiro participated in a global scientific study that revealed how rising temperatures can accelerate the decomposition of organic matter in wetlands, putting their ability to store carbon at risk. . The work, which studied wetlands in 28 countries and involved researchers within the international TeaComposition H2O network, was recently published in a scientific article in the journal Environmental Science and Technology.
The team, which included researchers Ana Sousa and Ana Lillebø from CESAM and the Department of Biology at the University of Aveiro, studied more than 180 wetlands around the world, from eight macroclimates and over three years, from coastal environments to freshwater ecosystems, using 19,000 tea bags as simple tools to measure the decomposition of organic matter in the soil. The marshes and sea grasslands of the Ria de Aveiro are part of the places studied and where bags of green tea and rooibos tea were “buried”. The results show that freshwater wetlands and salt marshes are those that best preserve carbon. However, rising temperatures are accelerating the decomposition of more resistant (recalcitrant) organic matter, which could reduce the ability of these areas to act as carbon sinks and contribute to mitigating climate change.
With temperatures rising, projections point to an increase of around 3% in decomposition rates by 2050. This effect, although small, could have important consequences for the global climate balance.
The study highlights the importance of protecting wetlands and understanding how local and global factors influence their ability to store carbon. International collaboration between researchers, including those from CESAM, and including such diverse wetlands from several continents, was essential to advance this crucial global knowledge to tackle climate change.
See the article “Climate Effects on Belowground Tea Litter Decomposition Depend on Ecosystem and Organic Matter Types in Global Wetlands”.
More information in the interactive Storymap, with the Ria de Aveiro as a case study